As telecommunication technology has progressed, though on one hand it has proved immensely beneficial for all, on other hand it has given rise to various types of frauds being done in these telecommunication networks. One such fraud is called termination bypass fraud where fraudsters change the termination leg of a call (mobile call or landline call) to avoid paying termination charge to a terminating operator for this terminated call. These calls can be international or national calls that are terminated at the terminating operator. As a result of this, operators need to conduct various roaming tests to identify such frauds in the telecommunication network.
In one of the previous patents from inventors of a referenced application, a solution has been provided for developing a “A single operator and network side solution for inbound and outbound roaming tests and discoveries of roaming partner services and frauds without involving remote probes or real roamer traffic”. This solution is hereinafter, referred to as “Predictive Intelligence” or “PI”.
The limitation of call generation based bypass detection methods today is that because they involve only test calls with test numbers, smart bypass fraudsters can examine the patterns of these test numbers and decide to blacklist them for future bypasses. Some of the patterns on these test numbers are either they are called too many times or they are not answered many times etc. As a result, the call generation methods lose their effectiveness in bypass detection. Even though more test numbers can be introduced, the same issue of getting detected by the bypass fraudster will rise again. Besides the fact that the test numbers are limited and each time they are used, it involves more work from the operators of these numbers, thereby creating a non-scalable solution.
Another previous patent from the inventors of this patent, titled “Advanced PI” was able to overcome the limitation of call generation based bypass detection method, by applying bypass detection in a stealth manner, thus making it difficult for fraudsters to detect that they are being tested. The Advanced PI patent was creating dummy subscribers, through signaling, as roaming agents to conduct these roaming tests. As the roaming agents were dummy subscribers there was no formal location area stored in MSC/VLR. In order to conduct these tests a virtual subscriber had to be created in the HLR, and for that a fake MT call was made to the VLR. As a standard process, the HLR would issue a PRN to the VLR to get MSRN of the subscriber. Now since the VLR does not have subscriber profile, it would issue a Restore Subscriber Data (RSD) message to HLR to get profile of the virtual subscriber restored. Since the subscriber's location info is not stored in VLR, some operators may want to avoid searching their complete network for the missing subscribers and may not return any MSRN.
Even when the operators page a location area to know the subscriber location, then the MSC has to page all location areas using Search MS message. This requires a lot of paging. In some cases, many MSC /VLRs may be shared/pooled, and the whole country may even share the same MSC. In such situation, in order to locate the subscriber, entire country would have to be paged, which is unrealistic. In some cases, it has also been observed, where PRN results in “system failure”, but RSD happens, therefore validity of the VLR, profile download, SMS etc. can be evaluated, not receiving any MSRN limits the missing control on voice calls.
It has been also observed during PI and Advanced PI deployments that large number of MSC/VLRs deviate from the “VLR restoration” standard. As a result of which, the VLRs do not allow MAP RSD. Statistically, more than 40% of VLRs today do not allow creation of virtual subscribers. Assuming that worldwide we have 2000 VLRs, then only 60% of them can be tested.
The PI deployment in general relies on Restoration Procedure standard. The procedure for restoring a subscriber profile is defined in the ETSI TS123.007 document. The procedure is complete—i.e. actually restore the subscriber profile using the RSD message—for a VLR: If the indicator “Subscriber Data Confirmed by HLR” is “Not Confirmed” the VLR requests authentication data, if required and still not available and subscriber data from the HLR.
However, the same procedure doesn't exist for SGSN—i.e. the RSD procedure does not exist for SGSN. In other words, while MT calls triggers a profile restoration from the HLR, there is no MT activity at SGSN having the same effect:                For the MT SMS: It rejects the SMS request and returns a failure report with cause value “Unidentified Subscriber” to the SMS gateway MSC indicating unsuccessful delivery of the SMS        For the MT user data session: When the SGSN receives a tunnel PDU for which no PDP context exists it discards the tunnel PDU and sends an Error indication message to the originating GGSN        For MT Paging via MSC/VLR (Gs interface): If the “SGSN-Reset” indicator is set to “false” and the IMSI is unknown or the MS is marked as GPRS or non-GPRS detached by the SGSN, the paging request is rejected.        
All these situations weaken the overall business case for using Advanced PI. In accordance with the foregoing, there is a need in the art of a system and a method for allowing an operator to conduct roaming tests using necessary intelligence to deal with above-mentioned problems.